How water quality changes as it passes through Life Monteverde Vogt 1 How water quality changes as it passes through Life Monteverde Stephanie Vogt Department of Earth Systems Science University of California, Merced EAP T ropical Biology and Conservation Program, Fall 2016 16 December 2016 ABSTRACT Life Monteverde is a 17 hectare coffee farm in Monteverde, Costa Rica. To irrigate their garden and to provide water for their small amount of livestock, they divert water from a nearby stream that begins at a spring about a kilometer uphill from the farm. The farm has a system to filter the water it uses from the stream before returning it to the watershed in an effort to return it in better quality than when the water was diverted. I studied the use of this water over seven study sites as it flowed through the farm. Twi ce a day for seven days I took measurements o f five water quality parameters: temperature, conductivity, total dissolved solids, dissolved oxygen, and pH. These parameters provided me with a comprehensive idea of the quality of the water flow in different areas of the farm. The water faced several points of contamination including a goat pen, a duck pond, and a pigpen. It also flowed through a series of ponds used to treat the water using floating hyacinth plants The goal of the study was to determine if t he farm returned the water it used to the watershed in better, worse, or similar quality, and what factors on the farm determined this quality. I found that the water quality did slightly decrease as it moved through the farm, but the filtering system func tioned well. The water got to the three filtering ponds at a slightly lower quality than when it was first diverted, but the first two ponds improved it back to the point of undisturbed water quality. However, there was one major contaminant the effluent from the biodigestor, which entered the water flow just before it was returned to the watershed. Therefore, the water was in slightly worse qual ity after the farm than before. Nevertheless, water quality was still within healthy ranges in the parameters st udied. Cambios en la calidad de agua cuando pasa a travs de Life Monteverde RESUMEN Life Monteverde es una finca de caf de 17 hectreas en Monteverde, Costa Rica. En esta finca desvan el agua de una quebrada cercada que comienza en una naciente un kilmetro cuesta arriba de Life para regar la huerta y proporcionar agua para el poco ganado q ue tienen. La finca tiene un sistema para filtrar el agua que utiliza de la quebrada antes de devolverla a la cuenca, en un esfuerzo por devolverla en mejor calidad que cuando el agua fue desviada. Estudi el uso del agua en siete sitios diferentes a trav s de la finca. Dos veces al da durante siete das tom medidas de cinco parmetros de calidad del agua: temperatura, conductividad, slidos disueltos totales, oxgeno disuelto y pH. Estos
How water quality changes as it passes through Life Monteverde Vogt 2 parmetros me proporcionaron una idea completa de la calidad del fl ujo de agua en diferentes reas de la finca. El agua tuvo varios puntos de contaminacin, incluyendo un corral de cabras, un estanque de patos, y un corral de cerdos. Tambin fluy a travs de una serie de estanques utilizados para tratar el agua utilizand o plantas de jacinto flotante. El objetivo del estudio fue determinar si la finca devolva el agua que utilizaba a la cuenca en calidad mejor, peor o similar que el agua entrante, y qu factores en la finca determinaron esta calidad. Encontr que la calida d del agua disminuy levemente mientras que flua a travs de la finca, pero el sistema de filtracin funcion bien. El agua lleg a los tres estanques de filtracin con una calidad ligeramente inferior a la primera vez que se desvi, pero los dos primeros estanques mejoraron la calidad al punto de no perturbada. Sin embargo, hubo un contaminante importante, el efluente del biodigestor, que entr en el flujo de agua justo antes de ser devuelto a la cuenca. Por lo tanto, el agua presentaba una calidad leveme nte inferior despus de su paso por la finca que antes de entrar en ella. Sin embargo, la calidad de agua estaba dentro de los rangos saludables en los parmetros estudiados. The health of a stream is important to the entire ecosystem in its watershed The have a negative or positive effect on the water quality of a stream, including many anthropogenic causes. In both the United States and in Costa Rica, agricultu ral use of water is a big source of pollution within watersheds. This pollution, often from agricultural runoff of pesticides and other chemicals used in the process, has several different dramatic effects on the water quality (Drury, 2013) The factors th at keep a stream healthy are very fragile and often change drastically due to natural changes in the environment. So when these streams are diverted from their natural courses and used in various agricultural or industrial processes, such as irrigation, w ater for livestock, and mechanized practices, it takes a large toll on the overall quality of the water (Drury, 2013) These pollution levels can be determined by testing some aspects of water quality; I tested five of these properties that are widely ac cepted to be good measures of the general health of the water in that given area. These five aspects are temperature, pH, conductivity, dissolved oxygen, and total dissolved solids. The general condition of streams and a quatic ecosystems are dependent on certain temperature ranges. Temperature is important because not only do organisms depend directly on it, but temperature also affects many other parameters in water, including dissolved oxygen, types of plants and animals present and the susceptibility o f organisms to parasites, pollution and disease (Drury, 2013) Causes of temperature change in water include weather conditions, shade pollution from urban sources and the condition of groundwater inflows. Water temperatures can fluctuate seasonally, daily, and even hourly, especially in smaller sized streams. Spring discharges and overhanging canopy of stream vegetation provides shade and helps buffer the effects of temperature changes (Pappani, 2016) Water temperature is also influenced by the quant ity and velocity of stream flow. The sun has much less effect in warming the waters of streams with greater and swifter flows than of streams with smaller, slower flows Water temperature is important to the health of a steam because it reduces the solubil ity of oxygen on which aquatic life depends
How water quality changes as it passes through Life Monteverde Vogt 3 and also can increase the toxicity of ammonia and other toxic substances For these reasons, it is important to protect the state's water from unnecessary warming ( Pappani 2016) A pH test measures the alkalin ity or acidity of water. A pH of 7 is neutral, below 7 is acidic and above 7 is basic. Acid rain, caused by auto exhaust or other pollutants, causes a drop in pH. Pollution from accidental spills, agricultural runoff and sewer overflows can also change t he pH. Since chemicals in the water can affect pH, it is an important indicator of wa ter that is changing chemically (i.e., being polluted) (Perlman, 2016) The pH of water determines the solubility and biological availability of chemical constituents such as nutrients (phosphorus, nitroge n, and carbon) and heavy metals. I n addition to affecting how much and what form of phosphorus is most abundant in the water, pH also determines whether aquatic life can use it. In the case of heavy metals, the degree to w hich they are soluble determines their toxicity ( Habitat Indicators of Stream Health 2016) The specific conductance test measures the ability of water to pass an electrical current. Inorganic dissolved solids such as chloride, sulfate, sodium, calcium an d others affect conductivity in water. High conductance readings can come from industrial pollution or urban runoff, such as water flowing from streets, buildings and parking lots ( Habitat Indicators of Stream Health 2016) Extended dry periods and low flow conditions also contribute to higher conductance. Organic compounds do not conduct electrical current very well, so something like an oil spill tends to lower the conductivity of the water. W arm water also has a higher c onductivity ( Pappani 2016) Dissolved oxygen (DO) refers to the level of free, non compound oxygen present in water or other liquids. It is an important parameter in assessing water quality because of its influence on the organism s living within a body o f water Oxygen is essential for both plants and animals, but high levels in water can be harmful to fish and other aquatic organisms (Drury, 2013) Nonpoint source pollution can decrease the amount of DO in water, which can be harmful to fish and other aq uatic organisms. The decomposition of leaf litter, grass clippings, sewage and runoff from feedlots decreases DO readings (Dissolved Oxygen, 2013) Water is a good solvent and picks up impurities easily. Dissolved solids refer to any minerals, salts, met als, cations, or anions dissolved in water. Total dissolved solids (TDS) comprise inorganic salts (principally calcium, magnesium, potassium, sodium, bicarbonates, chlorides, and sulfates) and some small amounts of organic matter that are dissolved in wate r (Drury, 2013) TDS in water originate from natural sources, sewage, urban run off, industrial wastewater, and chemicals used in the water treatment process, and the nature of the piping or hardware used to convey the water (Oram, 2014 ). My experiment inv olve s all of these aspects of water quality. I compare d the overall health of the water as it passes through Life Monteverde, a coffee farm in Monteverde, Costa Rica. I am interested in the water quality of this farm because it is possible that their treat ment of the diverted water they use to irrigate their crops and garden reenter s the watershed cleaner than when it was initially diverted. The farm uses an interesting water treatment method involving several ponds and a hyacinth plant that filters the wat er enough to be suitable for irrigation. These plants have specialized bulbs under the surface of th e water that take in the water and remove and store the pollutants. The bulbs can filter out organic and possibly bacterial contaminants (Hamilton, 2014) T hey are a floating relative of the water lily that have roots in standing water that naturally remove pollutants.
How water quality changes as it passes through Life Monteverde Vogt 4 The plants have been found to remove 60 80% of nitrogen and potassium from polluted water, as well as small particulate matter and organic deb ris (Hamilton, 2014) While this plant is frequently used to filter lightly polluted waters, such as the stream going through the coffee farm, these plants are also used to clean highly polluted industrial runoff water, containing heavy metals such as merc ury, silver, cadmium, chromium, copper, nickel, zinc, and lead (Hamilton, 2014) This plant species is a natural, sustainable, healthy, and safe way to filter harmful toxins out of runoff and streams. In summary, throughout my investigation, I would like to answer the question s Does the Life Monteverde Farm actually return the water it uses back to the watershed cleaner than when it diverted it? If no, why? If yes, how? MATERIAL AND METHODS I had seven study sites throughout the Life Monteverde Farm. They gave me a comprehensive look at the water quality as it flows through the farm. 1. Site 1, Kitchen Sink : Site number one is the sink in the main kitchen on the farm. The water here comes from the municipal aqueduct supplied by the town. This wat er flows into the farm kitchen, where the gray water then flows directly into the water flow used for other things on the farm. This provides a baseline water quality as well as an idea of what the quality of the municipal water is like in Monteverde. 2. Sit e 2, Waterfall : The second study site is the other source of the water that flows through the farm: a stream that starts from a mountain spring a kilometer uphill from the farm. Some of this water is diverted into the farm where its first stop is to flow o ver a small waterfall. This is where I tested this water source. 3. Site 3, Goat Pen : The third study site is the next stop for the diverted water: the goat pen. Testing the water here tell s me how livestock affects water quality because there are 14 goats o n the farm that use this pond as their drinking water source The water also flows over several waterfalls here; one as it enters the pond in the goat pen, and one as it exits. I took my measurements from the second waterfall. 4. Site 4, Duck Pond : From the g oat pen the water flows over several wide waterfalls that act as a filtering system for large pieces of organic matter. This is also the area where the water flow from the diverted stream combines with the gray water from the kitchen sink. These ponds are home to two ducks. To measure how this area overall affects the quality of the water flow, I took my measurements from a point a little downstream from the duck ponds; specifically, the waterfall as this water enters the next pond. 5. Site 5, Pond One : The fi fth study site is the uppermost pond in the farm garden, which I This pond maintained about 85 % plant coverage throughout my data collection period. This pond is also home to sev eral small fish. The water flows into this pond via a pipe that waterfalls over several rocks, and flows out and down a small stream to another waterfall into Pond Two. I took my measurements from this waterfall to get an idea of how the entire process of Pond One affects the water. 6. Site 6, Pond Two : Pond Two is the sixth study site. This is the middle pond and the largest, with the biggest number of hyacinth plants. The coverage of this pond is about
How water quality changes as it passes through Life Monteverde Vogt 5 90%. This is the second step in the treatment. The water flows in via a waterfall and out through a pipe underwater, which pours it into the next pond. I took my measurements for Pond Two at this point, right before the water entered Pond Three, to get a complete 7. Site 7, Pond Three : P ond Three is the l ast stop before the water flows back into the watershed via a small nearby secondary stream. There are two sources for the water in this pond. One is from the biodigestor, w hich is where the farm processes the waste from the pigpens into methane. The effluent water from this process flows into Pond Three. The water that comes in from Pond Two flows through a pipe that empties a few inches above the surface of the water, and exits through an underwater pipe that leads under a path and into a downhill stream that drains into the watershed. I took my measurements at the beginning of the small flow as the water heads towards the stream. This will tell me the final state of this water flow after it went through the farm, and will effectively an d will tell me how successful the water treatment of the hyacinth plants is I will be able to compare this measurement with the waterfall measurement from site two, to see how much the water quality changes from when the farm diverted the water from the w atershed, to when it returned it On the following page there is a diagram to depict this water movement through the farm. I used the YSI water quality reader to take measurements of temperature, conductivity, total dissolved solids, dissolved oxygen, and pH. I took two measurements a day for seven days (although on the first day of measuring I only took one) for a total of 13 data collection times. I took note of the weather and the exact time when I took each measurement To get each measurement, I took a sample of the water in a cup and brought it to the YSI meter so the measurements were as consistent as possible every time. I to ok these samples in the same order so that each sample was collected at roughly the same time each day I did the measurements approximately between 9 and 10 in the morning, and 1 and 2 in the afternoon.
How water quality changes as it passes through Life Monteverde Vogt 6 Municipal Aqueduct Kitchen Sink Mountain Spring Goat Pen Duck Pond Pond 1 Pond 3 Pond 2 Biodigestor Water Flow Through Life Monteverde Stream = Testing Site 2 1 3 4 5 6 7 Stream
How water quality changes as it passes through Life Monteverde Vogt 7 RESULTS In total, I took thirteen measurments over seven days from 16 November to 23 November 2016 The following graphs represent the sites as they appear in order as the water flows into, through, and out of the farm. Temperature Figure 1 T he average temperature values for all sites across the farm. The x axis represents the different sites while the y axis is the average temperature in degrees Celsius The error bars represent standard deviations The average temperature across the seven sampling sites was relatively consist ant at around 19.30 + SD 1.08 degrees Cels ius (Figure 1) There is a slight decrease in average temperature between sites five and six, and then an increase between sies six and seven. The highest average temperature was recorde d at site seven at 19.48 17.50 18.00 18.50 19.00 19.50 20.00 20.50 21.00 0 1 2 3 4 5 6 7 8 Temperature in degrees C Site Number
How water quality changes as it passes through Life Monteverde Vogt 8 Conductivity Figure 2 C onductivity throughout all seven testing sites. The cond uctivity is measured in micro S ie mens per centimeter The error bars re present standard deviations. The above graph ( Figure 2 ) shows fairly consistant values of conductivity for each site throughout the farm. The lower the value for conductivity, the better the quality of the water. The average value for the kitchen sink is much lower than those from the water from the watershed, recorded at an average of 97.85 mS/cm, showing that that water coming from the municipal aquedeuct is of slightly bette r quality. The values in sites five a nd seven were slightly higher than the others, showing a decrease in water quality in these sites. Sites two and three, which are the waterfall (where the water is diverted from the stream to the farm) and the water source in the goat pen, have very small standard deviations, which means that every time I took measurements from these locations the value for conductivity was very similar. 80.00 90.00 100.00 110.00 120.00 130.00 140.00 150.00 160.00 170.00 0 1 2 3 4 5 6 7 8 Conductivity in S/cm Site Number
How water quality changes as it passes through Life Monteverde Vogt 9 Total Dissolved Solids Figure 3 Total Dissolved Solids (TDS) for each site. TDS is measu red in grams per liter. The error bars represent standard deviation This graph shows findings consistant wit h prev iou sly discussed findings (Figure 3) The lower the value is for Total Dissolved Solids, the better the water quaility is determined to be. T he water quality of the water from the kitchen sink, at site one, is somewhat higher than that of the water from the divered stream. The rest of the TDS values change slightly as t he water moves through the farm. T he readings are marginally higher at sites five and seven, with fairly consistant numbers throughout the farm There was a significant difference where the water enters and exits the farm, that is, sites 2 and 7 ( t(24) = 2.24, p = 0.03 ). 0.050 0.060 0.070 0.080 0.090 0.100 0.110 0.120 0 1 2 3 4 5 6 7 8 Total Dissolved Solids in g/L Site Number
How water quality changes as it passes through Life Monteverde Vogt 10 Dissolved Oxyg en Figure 4 T he average values for dissolved oxygen (DO) in each site. DO is measured in percent The error bars represent standard deviation The trend in the dissolved oxyg en levels is slightly downward with some variation (Figure 4) This means that the dissolved oxygen level gets lower as the water moves through the farm. The kitchen sink and the goat pen, at sites 1 and 3 respectively, are the highest values, at about 82.5% The lowest values were found at sites four and six, which were the duck pond and the second pond in the series of three filtering ponds. These areas had an average value of about 69%. This means the range of percent dissolved oxygen within these seven sites was about 13.5%. The trend is consistant wit h previous findings; sites five and seven are slightly elevated with a decrease in sites four and six. ( t(24) = 3.30, p = 0.003 ). 60.00 65.00 70.00 75.00 80.00 85.00 90.00 0 1 2 3 4 5 6 7 8 Dissolved Oxygen Percent Site Number
How water quality changes as it passes through Life Monteverde Vogt 11 pH Figure 5 T he average values for the pH level of each site. The error bars represent standard deviation The pH scale goes from 1 14 with 7 being neu tral and anything above 7 basic and anything below 7 acidic. The values of pH are the least consistant of all my readings (Figure 5) They fluctuate throughout every site. The filtered water coming from the kitchen sink has an average value of 6.49 which is the more acidic than every other reading. The most basic water was found at the goat pen with a pH level of 7.07. Site number four, the duck pond, had very inconsistant readings and so it has a big standard deviation. The familiar patterns of similar readings from sites five and seven and then an opposite trend in site six are present Again, sites 2 and 7 were significantly different ( t(24) = 4.15, p = 0.0004 ). 6.30 6.40 6.50 6.60 6.70 6.80 6.90 7.00 7.10 7.20 0 1 2 3 4 5 6 7 8 pH Value Site Number
How water quality changes as it passes through Life Monteverde Vogt 12 Morning versus Af ternoon Figure 6 T he average temperature for each site for the readings taken between 9 10am, and for the readings taken between 1 2pm. The temperature is on the y axis and is shown in degrees Celsius. The error bars represent standard deviation. A clear trend in the average temperatures between the morning and afternoon for each site is depicted in Figure 6 I n each of the sites the afternoon temperature readings were warmer than the ones in the morn ing by at least half a degree, sometimes more than a full degree Celsius. The average difference between the morning and afternoon readings for each site is 1.07 degrees Celsius. 17.00 17.50 18.00 18.50 19.00 19.50 20.00 20.50 21.00 21.50 22.00 1 2 3 4 5 6 7 Temperature in C Site Number Afternoon Morning
How water quality changes as it passes through Life Monteverde Vogt 13 Figure 7 A verage dissolved oxygen for each site for the readings taken between 9 10am, and for the readings taken between 1 2pm. The graph depicting the average values for dissolved oxygen in the morning and afternoon (Figure 7) does not have any clear trends when comparing the two different times of day. The points on the graph that represent the different times of day are often ov erlapping each other The standard deviations for each point are relatively consistant except for site 4, the duck pond, which has an unsually large standard deviation 50.00 55.00 60.00 65.00 70.00 75.00 80.00 85.00 90.00 95.00 1 2 3 4 5 6 7 Dissolved Oxygen in Percent Site Number Afternoon Morning
How water quality changes as it passes through Life Monteverde Vogt 14 Sunny versus Cloudy Figure 8 This graph shows the average temperature for each site on sunny and cloudy days. The temperature is on the y axis in degrees Celsius. The error bars represent the standard deviation for each average shown. There is a relationship between the weather and the water temperature (Figur e 8). In every site except one, the readings taken on cloudy days were warmer than those taken on sunny days. The average temperature on cloudy days was 19.46 degrees, and those on sunny days were a little less at 19.12 degrees, for a difference of 0.34 de grees. While the pattern was mostly consistent through the sites, the difference in values was not very significant. Site 7 did not follow the trend, with the average measurements taken on sunny days 0.13 degrees warmer than those taken on cloudy days. 17.00 18.00 19.00 20.00 21.00 1 2 3 4 5 6 7 Temperature in C Site Number Sunny Cloudy
How water quality changes as it passes through Life Monteverde Vogt 15 Figure 9 A verage dissolved oxygen for each site on sunny and cloudy days. The dissolved oxygen is on the y axis in percent The error bars r epresent standard deviation. The relationship between dissolved oxygen levels and weather is not very apparent (Figure 9). While six of the seven sites showed that measurements taken on sunny days were slightly higher than those taken on cloudy days, this was only by an average of 2.0 6%. The one site that had an opposite result with higher readings of dissolved oxygen on cloudy days had a large standard deviation, meaning that the readings were inconsistant throughout the data collection period. 50.00 55.00 60.00 65.00 70.00 75.00 80.00 85.00 90.00 95.00 1 2 3 4 5 6 7 Dissolved Oxygen in Percent Site Number Sunny Cloudy
How water quality changes as it passes through Life Monteverde Vogt 16 DISCUSSION Temperature According to the Monteverde Adopt A 2010 Annual Technical Report, the average temperatrue for streams in the Monteverde area for the month o f November is 17.63 degrees Cels ius. However, t he streams tested in the Technical Report did not include th e exact stream that is diverted for the use of the farm (Elmore and Welch 2010) directly from the watershed) was slightly higher than this number, that could be due to a number of reasons, including elevation, sun exposure, and pollution upstream from Life Monteverde. The average temperature level in site 7 was the highest of all the sites. This was due to the fact that the effluent from the biodigestor ran directly into this pond, decreasing the water quality. The World Health Organization has put together a collection of restrictions and guidelines from 100 countries and territories across the world and created comprehensive recommendations for water quality parameters. According to this source, water temperature needs to b e between 15 and 35 degrees Cels within these parameters, meaning the temperatue of the water flo wing through the farm is at no time at a dangerous level. Conductivity Conductivity level is impo rtant in stream health because excessive amounts encourage algal growth which can lead to wide daily fluctuations in both pH and dissolved oxygen levels wh ich are known to be harmful to aquatic life Thick growths of algae also exclude certain invertebrate species and there is an overall degradation of waterways in both biology and appearance ( Habitat Indicators of Stream Health 2016) In larger streams and rivers, periodic high flows of water velocity can flush out algal growth. However, in small farm streams the degradation may be less easy to reverse ( Habitat Indicators of Stream Health 2016) This affect may be present in Life Monteverde. According to t he National Institute of Water and Atmospheric Research (NIWA), an is 50 to 149 mS/cm ( Habitat Indicators of Stream Health 2016) All of the averages of each report on international restrictions on conductivity suggests values around 170 mS/cm, and my data suggests the water tested exceeds t hat expectation (Drury, 2013) The Monteverde Institute Technical Report found an average of 133.03 mS/cm in several streams in the Monteverde area in the month of November (Elmore and Welch, 2010). This is very consistant with the level of conductivity in the water from the diverted stream, tested at site two, the waterfall, which was 129.15 mS/cm. Total Dissolved Solids The WHO suggests a range of 0. 0 2 to 1 g/L for healthy water, and this water again exceeds this recommendation (Drury, 2013) TDS is closely related to conductivity, which is why both paramaters suggest such healthy water and also follow a similar pattern throughout the data. The filtered water coming from the kitchen sink again had the best
How water quality changes as it passes through Life Monteverde Vogt 17 water quality accroding to TDS. The three fi ltering ponds followed a parallel trend as the prevous measurements Pond One was slightly elevated, the values for Pond Two fell, and then increased again in Pond Three. This can be attributed to the success of the filtering system and the effluant water from the biodigestor being added directly into Pond Three, lowering the water quality. Dissolved Oxygen The WHO suggests a range of dissolved oxygen to be between 4 8mg/L (Drury, 2013) All of my data points for every site fal l within this range The range of the averages of the dissolved oxygen is 6.38mg/L and 7.62mg/L with an average of 6.98mg/L. O ther sources also suggest this water is within a healthy range for dissolved oxygen The Water Research Center recommends disso lved oxygen should be above 5mg/L for the prime conditions for aquatic life with 9mg/L and above being ideal (Oram, 2014). The Monteverde Technical Report found that the average dissolved oxygen values for streams in the Monteverde area for the month of November was 7.58mg/L, which is fair ly consistant with my findings of the water at the farm (Elmore and Welch, 2010). pH Since the pH values were the least consistant of all the measurements it is more difficult to draw conclusions from my numbers. The WHO report suggests the values should be between 6.5 and 8.5 (Drury, 2013) The NIWA has more strict guidelines with a Habitat Indicators of Stream Health 2016) All of my average readings for each site fall wit hin this range. The average pH value across all sites was 6.83. The pattern in my graph showing pH (Figure 5) is not very consistant with the patterns of other parameters. The graph shows a sharp incline from sites one to three followed by a gradual decl ine from sites three to seven. The standard deviation from site four, the duck pond, is very large. This may be explained by the different contaminents added to the water throughout the farm. Livestock, such as goats and ducks, can have a large and varying affect on water quality including pH levels. Morning versus Afternoon I took my measurements for each site twice a day, o nce in the morning and once in the afternoon. I used this method for several reasons; this allowed me to get more data points in a shorter period of time, and some of the water quality parameters I tested change throughout the day due to varying levels of sunlight and air temperature. I compared two of the five parameters I tested; water temperature and dissolved oxygen. The trend in the temperature was clear. The average temperature for all sites in the morning was 18.72 degrees vs 19.79 degrees in the aft ernoon. As the day went on and the sun rose in the sky, it warmed the shallow water in the streams and increased the temperature at every site. This result was to be expected. The dissolved oxygen had less of a trend. The average value in the morning was 75.46% versus 75.81% in the afternoon. While this difference is not significant, it is still important; this data supports the fact that dissolved oxygen levels do not depend on the time of day, sun position, or air temperature very much.
How water quality changes as it passes through Life Monteverde Vogt 18 Sunny versus Clo udy My data supported the theory that testing water parameters does depend marginally on the weather. The temperature on sunny and cloudy days did show a pattern that the water is warmer on cloudy days. This may be due to the fact that clouds often act as insulation for the atmosphere, making the air temperature warmer than it would be on clear, sunny days. Water temperature reflects the air temperature so this could explain the pattern in my data. The dissolved oxygen comparison of sunny and cloudy days has less of a trend. The dissolved oxygen was slightly higher on sunny days. This could be attributed to the above phenomonon as well because dissolved oxygen levels and temperature are positively correlated Conclusion None of the sites within the farm conta mina nts, namely sites three and four, had a substantial e ffect on the quality of the water. While it is true that the health of the water gradually and slightly decreased as it flowed through the farm, it was not one specific site that I tested that majorly decreased the quality of the water all at once My data supports the theory that the filtering system of the hyacinth plants do in fact work to increase the quality of the treated water. Al l five of the parame ters I measured suggested that the wate r quality increased from Pond One to Pond Two I believe that the quality would have continued to increase through Pond Three if not for the water from the biodigestor, a major contaminent, that flows directly into Pond Three This water therefore does not have enough chances to be filtered enough before being returned back to the watershed. The measurements I took from site two, the waterfall, represent the state the water is in when it is first diverted from the stream, before the farm has any effect on the water. T hese measurements can be compared to site seven, which was measured the water left Pond Three to run directly down into a downhill stream, to get a comprehensive view of how the farm as a whole affects the water quality. All five of the parameters measured suggested that the water quality decreased between these two sites, but only slightly. I preformed a t test comparin g all the values from sites two and seven for three of my paramete rs (total dissolved solids, dissolved oxygen, and pH). Each of these t tests returned a p value lower than 0.05, meaning that and the values from site seven were statistically significantly lower than those taken at site two. To answer my original research question of how does the water being returned to the watershed compare to when it was diverted, my results suggest the water quality is worse, but not by much, and that the biggest factor in this water quality is the biodigestor. Howe ver, while the quality does decrease, it does reamin within healthy ranges for each parameter. I maintain that if the outflow from the biodigestor were to be moved from Pond One to someplace highger up in the system of water flow it is possible the farm c ould return the water to the watershed at the same or even slightly better quality than when it diverted it.
How water quality changes as it passes through Life Monteverde Vogt 19 ACKNOWLEDGEMENTS I would like to first and foremost thank S ofia Arce Flores and Justin Welc h for providing me wi th constant ideas, support, a dvice, and cute baby looks for the entirety of this project. I have learned so much from you both, not only about water quality but also about how to properly conduct a real research project and create a scientific report. I also owe much of my success to Guillermo and Daniel Vargas, among other staff, at Life Monteverde. Thank you for helping me with all my questions and teaching me and many others about the rich process of coffee, from soil to cup. Also, thank you Daniel for finally finding me a sloth. An d finally, thanks to my Finca Famil y; Ari, Kristen, Sofia, and Boro na, for supporting me every day on our commute to and from the farm and for providing me with endless entertainment all day. The experience would not have been the same without each of you! LITERATURE CITED Anon, 2006. Guidelines for Drinking water Quality 4th ed., Geneva: World Health Organization. Anon, 2016. Dissolved Oxygen. Environmental Measurement Systems. Available at: http://www.fondriest.com/environmental measurements/parameters/water quality/dissolved oxy gen/ Anon, 2016. Habitat indicators of stream health. NIWA. Available at: https://www.niwa.co.nz/our science/freshwater/tools/shmak/manual/9habitat. Anon, 2016. Mo nitoring 101. Available at: http://www.iwla.org/conservation/water/save our streams/monitoring 101. Drury, D., 2013. Report on Regulations and Standards for Drinking Water. Available at: http://www.who.int/water_sanitation_health/Draft_RegScan_May_2014.p df. Elmore, B. and J. Welch, 2010. Physical, Chemical & Biological Conditions Of Surface Waters In Monteverde, Costa Rica. Monteverde Adopt A Stream Program. Available at: http://monteverde institute.org/assets/files/Adopt A Stream%20Reports/Technical_Report_2009 2010_Monteverde%20Adopt A Stream.pdf. Hamilton, G., 2014. Striking a Deal with the Weed from Hell. Conservation Magazine. Available at: http://conservationmagazine .org/2014/03/water hyacinth in kings bay/. McKnight, J., 2014. Water and Health in the Nandamojo Watershed of Costa Rica Community Perceptions towards Water, Sanitation, and the Environme. University of South Florida. Oram, B., 2014. Dissolved Oxygen. Dr inking Water Quality. Available at: http://www.water research.net/index.php/dissovled oxygen in water.
How water quality changes as it passes through Life Monteverde Vogt 20 Oram, B., 2014. Total Dissolved Solids. Drinking Water Quality. Available at: http://www.water research.net/index.php/water treatment/tools/total dissol ved solids. Pappani, J., 2016. Common Water Quality Measures. Available at: http://www.deq.idaho.gov/water quality/surface water/water quality criteria/common measures/. Perlman, H., 2016. pH: Water properties. USGS Water Science School. Available at: ht tp://water.usgs.gov/edu/ph.html.